Dyestuffs of the anthraquinone series



Patented Aug. 31, 1948 DYESTUFFS OF THE ANTHRAQUINONE:

, SERIES- Y t Ernst Gutzwiller, Basel, Switzerlandfassiignor to 1 Sandoz Ltd., Fribourg, Switzerland, a Sw iss H Nb Drawing. Application M rch 9, m sjserialf No; 581,957. In Switzerland September 30, I

Section 1, Public Law 690; Augus't s, 1943 1 Patent expires September 30;,"1963" Thepre'sent invention relates to new dyestuffs of the anthraquinone series, which dye animal fibres into blue to green shades, possessing excellent fastness properties and to the process for their manufacture.

According to U. S LetterS Patent No. 2,042,757, acid dyestuffs'can be preparedby the condensation of polynuclear amines with anthraquinone compounds whichcontain in positions l and 4 groups capable of beingsubstituted.

It has now been found that very valuable new acid dyestuffs can be obtained by condensing 2- amino-l 2 3 :4-tetrahydronaphthalen with anthraquinone compounds which contain in positions 1 and 4 groups capable of being replaced by the amine and which are substituted in 6- and/or l-positionb'y halogen, and-"bysubsequen'tly sulfonating the resultant condensation products.

Illustrativ of anthraquinone compounds which are suitable 'forfthis condensation are 6:7-dichloroquinizarine, 6 7-dibromoquinizarine, 6 7- bromo-chloroquinizarine, 6 7-dichloro-1 4-hydroxyaminoanthraquinone,' 6 7-d ichloro- 1 4-diaminoanthraquinone and the leuco-derivatives of these compounds, Furthermore, polyhalogenated anthraquinone compounds such as 1:416:7- tetrahalogenanthraquinone may also be used.

The condensation of the anthraquinone compound with the amine is carried out preferably in presence of a solvent and of condensing agents like boric acid and; copper salts. Of course, the amine.can-be.usedsimultaneously as solvent. On the'otherhandjhigli'bbiling alcohols, like amyland benzyl-alcehol;- methylhexaline or other organic solvents, can be used as inert solvents. H

The condensation is "generally car O f at temperatures over 100 C. and is maintained until starting anthraquinone compound can no longer be detected in the condensation mixture, Generally',' a' mixture of anthraquinone andleucoan thraquinone compounds is used;;when' theconidensation is finished; the leucg compound thus produced'is oxidised by'means ofan air stream, preferab'yin presence'offan alkaline compound and of a copper'derivative'i The isolation'of the new lconden's'ation products is carried out accordingtothe methods generally used for the manufacture 'ofanthraquinoneeompounds and the "sulphon'atiorf or the insoluble products is carried out preferably with sulphuric acid monohydrate or with sulphuric acid containing about -10% of sulphuric acid anhydride.

The following examples, without being limitatiVe, illustrate the present invention, the parts being by weight.

, 4 clai (01. 260-371) V Example-1 :20 ,parts of leuco-6:7-bromochloroquinizarine and; '120 parts of 2-amino-1:213:4:tetrahydrovnaphthaleneare stirred together at 120.150 C., until the condensation is finished. After. oxidation with an air stream, whichmay take place in presence'of some piperidine and copper acetate, the condensation product is precipitatedby diluting the charge with ,120 parts of ethanol and filtered ofi. Eyre-crystallisation from an organic solvent itcan becompletely purified. (By'treating this base with 4-6 times it 'weight'ofsulphuric acid monohydrate at 020 C., a dyestuif will be obtained dyeing wool in very fast brilliant'blue shades- I 1 j 'Examplez 1( :parts of .leuco-G:7-dichloroquinizarine, 10 parts of 6: 7-dichloroquinizarine, 10 parts of boric acid and parts of 2-amino-1:2:3:4-tetrahye dronaphthaleneare stirred together at 120-150 0., until the condensation is finished. Afteroxidationwith an air stream the condensation prodnot is precipitated by dilution with parts of ethanol and isolated by filtration. Dark crystals being-soluble in organic solvents with a greenishblue shade will thus be obtained. By treating the base with-4-8times its weight ofsulphuric acid monohydrate: at;v 0 -20 C. a dyestuffwill b obtained-whichdyes wool in brilliant greenish-blue shades.

Example 3 20 parts of leuco-Gz'l-dichloroquinizarine and 100 parts of 2-amino-122:3:4-tetrahydronaphthalene are heated at 100-150 C. under good stirring and in absence of air until the condensation is finished. After oxidation by means of an air stream, which may take place in the presence of some piperidine and copper acetate, the reaction product is precipitated by means of an addition of 100 parts of ethanol, filtered and washed with ethanol. After crystallisation from an organic solvent like pyridine, aniline, nitrobenzene or methylhexaline, the base can be obtained in a pure form. By treating this base at 0-30 C. with 4 to 6 times its weight of concentrated sulphuric acid or sulphuric acid monohydrate a dyestuii will beobtained that dyes animal fibres and nylon in beautiful blue. shades of excellent fastness properties.

Instead of leuco-6:7-dichloroquinizarine, a mixture of 6:7-dichloroquinizarine with leucofiz'l-dichloroquinizarine may also be used. The condensation can also be carried out in the presdiluted hydrochloric acid. After heating for "ashort time, the base is filtered off, washed out with hot water and dried. The :raw base thus-obtained is then taken up in a solvent, like nitrobenzene, aniline, pyridine, quinoline, tetraline,

dichlorobenzene or methylhexaline, heateduptoa higher temperature and treated with an" air stream blown on the surface of the liquid. After dilution with ethanol and addition 'rofsomecausttc soda lye, the base can be obtainediinpureatorm.

Example 4 10 parts of leuco-6-chloroquinizarine, 10 parts of 6-chloroquinizarine, ,10 parts of boric acid and 120 parts of 2-amino-15213':4-tetrahydronaphthalene fare stirred together at '120--150-'C. until the @On dQhSQlfilOIi is fin'ished. After oxidation with an air stream the condensation mass is adiluted with l50p'arts of ethanol and the base'thus precipitated separated by filtration. Bronzing crystals will be Obtained which are soluble in organic solvents with a blueco1ora'tion. By-treating the condensation product with 4-8 times its weight of sulphuric acid monohydrate at -20 C. a .dyestufl will 'ber'obtained that dyes Wooliln very brilliant blue shades.

Erampl fi 20 parts of leuco-fi-chloroquinizarmetillm'iparts of the carbonate of vZ-amino-lzzziiz l-tetrahydronaphthalene and 80 parts of methylhexaline are heated in absence of air'at 100 150 Chm-til the condensation is finished. The isolation of the base- 1s -'carried :out in the usual way; whereby a compound :w ill be obtained identical with-that described in Example 4.

Instead of methylhexaline, other diluting agents, like amyl alcohoL-benzyl alcohol, etc. can

qui-none and also the mixtures of the said --compounds with leuoo-S-chloroquiniza-rl-ne and- 8- chloroquinizarine.

What I claim is:

1. An anthraquinone dyestufi .of the formula wherein one X is a :member selected from the group consisting :of chlorine and bromine, and

the other X is a member selected from the group consisting .of hydrogen, chlorine and bromine.

2.1 An anthraquinone dyestulf :ot theiformula wherein X is a member of the group consistin of chlorine and bromine.

.3. anthraquinone dyestufi of that-formula IERNST"'GUTZWIIIIIERJ REFERENGES- CITED 7 y The. fiollowingtzreferences are of recordiin the file oflthis patent:

UNITED PAWI'EN'ETS 1 Number Name "Date .1,8.7.'I,900 Kronholzl.. l ...Sept. #20, 1932 210.42.37.55? .Zahn et .al. June-2, 1936 2,204,748. IBuxbaum June .18, .1940 2,315,.788' Gutzwiller Ann-6,1943 2,377,145 Gutzwiller- .May 29,- 194.5

FOREIGN @PATENTS Number Country Date 158 9143' "Switzerland Jan. 1651933 

